U.S. patent number 3,934,497 [Application Number 05/461,501] was granted by the patent office on 1976-01-27 for apparatus for cooking fruit and the like products.
This patent grant is currently assigned to California Fruit Concentrates, Inc.. Invention is credited to Phillip L. Hannah.
United States Patent |
3,934,497 |
Hannah |
January 27, 1976 |
Apparatus for cooking fruit and the like products
Abstract
An apparatus for cooking fruit and the like products includes a
tank or cooking chamber disposed for receiving a quantity of such
products and a quantity of water sufficient to cover the products
therein and sufficient enough to create the necessary back pressure
for a hydraulic head and sufficient enough to provide an adequate
medium for agitation. Steam is supplied to the lower portion of the
tank to raise the temperature of the water to a cooking temperature
of the products submerged therein, which temperature may be the
boiling point of water. Steam or moisture laden vapor which escapes
to an upper surface of the body of water is recirculated under
pressure to a lower portion of the tank, such that it will be
redirected into the cooking area. Such recirculation is performed
by a conduit and a blower or pump mounted in the path of the
conduit. The conduit has an inlet above the level of the water in
the tank and an outlet below the level of the water adjacent a
bottom wall of the tank. The pump effectively increases the
pressure of the steam and thereby increases its temperature. A
method of cooking fruit and the like products includes submerging
such products in a body of water, passing steam through the body of
water until it is heated to the cooking temperature of the
products, and recirculating under pressure the steam or moisture
laden vapor which escapes from an upper surface of the body of
water to a lower level thereof.
Inventors: |
Hannah; Phillip L. (San Jose,
CA) |
Assignee: |
California Fruit Concentrates,
Inc. (San Jose, CA)
|
Family
ID: |
23832807 |
Appl.
No.: |
05/461,501 |
Filed: |
April 17, 1974 |
Current U.S.
Class: |
99/476; 99/477;
126/348; 422/281; 426/510; 126/20; 126/369; 426/407; 426/523;
137/599.14 |
Current CPC
Class: |
A47J
27/16 (20130101); Y10T 137/87362 (20150401) |
Current International
Class: |
A47J
27/16 (20060101); A47J 027/026 (); A47J 027/04 ();
A47J 027/16 () |
Field of
Search: |
;99/473-477,403
;126/348,369,377,20 ;23/290.5 ;426/510,407,511,509,523,521
;137/599.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Lutter; Frank W.
Assistant Examiner: Greenblum; N.
Attorney, Agent or Firm: Wiseman; Jack M.
Claims
I claim:
1. Apparatus for cooking fruits and the like products in which said
fruits are immersed in a body of water to form a slurry, said body
of water being sufficient to cover said products to form said
slurry and to create the necessary back pressure for an hydraulic
head and of sufficient quantity to provide an adequate medium for
the agitation of said slurry, said apparatus comprising:
a. a closed tank disposed for receiving said slurry in a lower
portion thereof,
b. first means for introducing steam into the slurry contained in
said tank for bringing said slurry approximately to a cooking
temperature,
c. recirculating means for recirculating under pressure any
moisture laden vapor which escapes from an upper surface of the
slurry to a lower portion of said tank and into the slurry for
heating said slurry and for agitating said slurry, said
recirculating means being separate and apart from said first
means.
2. The apparatus of claim 1, wherein said tank includes a confined
space above the upper surface of the slurry contained therein; and
said recirculating means includes a conduit extending from said
space to a lower portion of said tank, and means for advancing
moisture laden vapor under increased pressure through said conduit
for increasing the temperature of the advancing moisture laden
vapor.
3. The apparatus of claim 2, wherein said advancing means includes
a pump mounted in the path of said conduit.
4. The apparatus of claim 3 and further comprising a check valve
mounted in the path of said conduit between said pump and the lower
portion of said tank.
5. The apparatus of claim 2, wherein said recirculating means
includes a member mounted in the lower portion of said tank and
having a plurality of apertures therein, said member being secured
to the end of said conduit extending to the lower portion of said
tank, such that moisture laden vapor will be introduced into said
slurry at spaced locations.
6. The apparatus of claim 1, wherein said first means includes a
conduit having a first valve for controlling the flow of steam
therethrough, and a by-pass conduit having a second valve for
controlling the flow of steam therethrough and connected in
parallel with said first valve.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to an apparatus for and a method
of cooking fruit and the like products, and more particularly to
such a cooking apparatus and method which employs steam as a heat
exchange medium and as an agitating agent.
2. Prior Art
Steam has been employed extensively for heating and cooking various
products. Steam has also been employed in the past for cooking
fruit and similar products, such as dates, figs and prunes, for the
purpose of liberating the sugar content of such products. The
cooking process softens the fruit until it ruptures and exposes the
pulp of the fruit to boiling or hot water, thereby liberating, over
a predetermined cooking time, the sugar content of the fruit to the
water. The resultant homogeneous mixture is refined and dehydrated
to a desired fixed level for various commercial purposes. Examples
of cooking apparatus which employ steam as a heat exchange medium
are found in U.S. Pat. Nos. 1,174,721; 2,885,294; 1,565,282;
474,009; 1,711,729; 1,539,309; 2,020,309; 2,143,903; 2,589,288;
2,654,734; 3,374,096; 3,224,881; 3,764,708; Re.19,868; 3,139,345;
and 1,955,289.
Previous methods of cooking fruit and the like products with the
steam as the heat exchange medium have been either excessively
expensive because of fuel costs or exceedingly slow. In order to
obtain a high volume of production, such products must be cooked at
the boiling point of water under turbulent conditions for short
periods of time. If the cooking time is enlarged, it is likely that
the products being cooked will be scorched, thereby effecting the
flavor of the finished product. Although this method of cooking
fruit produces a relatively high volume production, it requires and
consumes relatively large amounts of fuel.
In the cooking of fruit and the like products, the heat may be
applied as live steam in direct contact with the products or may be
applied indirectly through a heat exchanger. Such indirect heating
methods include, for example, the use of closed steam coils,
heating compartments in the bottom of a tank, or jacketed tanks.
Closed steam coils and jacketed type cooking chambers have distinct
disadvantages in that the coil or jacket tends to collect and burn
the products being cooked on the heated surface thereof.
Furthermore, such devices contribute very little to the agitation
that is required to rupture the fruit and expose its pulp to the
boiling or hot water in which it is submerged. Accordingly, such
devices require mechanical means for producing agitation of the
product slurry. Such mechanical agitation is generally unsuccessful
due to the presence of a foreign material and pits generally found
in raw fruit which material may cause damage to the agitation
elements.
By applying live steam which passes through the water in which the
products are submerged and by maintaining such water at its boiling
point, agitation is enhanced. The velocity of steam escaping from
jets in a bottom portion of a cooking tank and the turbulence
caused by boiling water generates sufficient agitation to aid in
the rupture of the fruit to expose its pulp. This cooking method is
capable of producing a relatively high yield in a relatively short
time period. It also requires and consumes relatively large amounts
of fuel, since a considerable amount of heat is lost by evaporation
from the surface of the slurry. Moisture laden vapor or steam
necessarily escapes from the surface of the slurry and is vented to
the atmosphere, thereby creating a relatively large heat loss. This
heat loss must, of course, be resupplied to the slurry to maintain
its cooking temperature.
SUMMARY OF THE INVENTION
It is, therefore, one of the primary objects of the present
invention to provide an apparatus for and method of cooking fruit
and the like products, which apparatus and method recover heat
losses and reapply such heat to the cooking chamber.
Another object of the present invention is to provide a cooking
apparatus for fruits and the like products which is capable of
performing the cooking process in a minimum amount of time and with
a minimum amount of fuel for generating heat.
Still another object of the present invention is to provide a
cooking apparatus for fruit and the like products which does not
require the use of any mechanical means for agitating the slurry
being cooked.
A further object of the present invention is to provide a cooking
apparatus for fruit and the like products in which heat is applied
thereto in the form of live steam in direct contact with the slurry
containing the products to be cooked.
These and other objects of the present invention are obtained by
the provision of a closed tank which is disposed for receiving a
slurry containing the products to be cooked and a quantity of
water, means for introducing steam into the slurry contained in the
tank, and means for recovering heat loss resulting from evaporation
from the surface of the slurry and the steam or the moisture laden
vapor escaping therefrom and reapplying such heat under pressure to
the slurry.
A feature of the present invention resides in the provision of
recirculating means for transporting any steam or moisture laden
vapor which escapes from an upper surface of the slurry to a lower
portion of the tank and introducing such moisture laden vapor or
steam under pressure to the slurry, such that the heat contained
therein is transferred thereto.
Another feature of the present invention resides in the provision
of means for increasing the temperature of any steam or moisture
laden vapor which is recirculated, such as a fluid pump which
increases the temperature of the steam or moisture laden vapor by
increasing the pressure thereof.
It is readily apparent that the present invention provides the
distinct advantage of recovering heat losses and resupplying such
heat to the slurry being cooked, such that a considerable savings
can be realized in the amount of fuel required to produce the heat
necessary for the cooking process.
The invention, however, as well as other objects, features
advantages thereof which will be more fully realized and understood
from the following detailed description, when taken in conjunction
with the accompanying drawing, wherein:
DESCRIPTION OF THE DRAWING
The single FIGURE of an elevation view, partially in section and
partially broken away, of a cooking apparatus constructed in
accordance with the principles of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the single FIGURE in the drawing, there is shown
a cooking apparatus constructed in accordance with the principles
of the present invention, which is generally designated with the
reference numeral 10. The cooking apparatus includes a tank 12
which forms a cooking chamber and is disposed for receiving a
quantity of fruit and the like products therein and a quantity of
water to form a slurry which is designated with the reference
numeral 14. The tank 12 is only partially filled with the slurry 14
to a level which is designated with the reference numeral 16, such
that a chamber 18 is provided in an upper portion of the tank 12. A
bottom wall 20 and a top wall 22 of the tank 12 are conically
shaped. A door 24 is provided in the top wall 22 to permit the tank
12 to be filled with the slurry 14. A conduit 26 extends from the
bottom wall 20 and may be provided with a valve or plug 28 therein
permitting the removal of the slurry 14 from the tank 12 after it
has been cooked.
A conduit 30 is provided with a valve 32 therein and extends into
the tank 12 through the bottom wall 20 thereof. The conduit 30 is
disposed for supplying steam from a steam supply (not shown) into
the tank 12 to heat the slurry 14. A by-pass conduit 34 having a
by-pass valve 36 therein is connected in parallel with the valve 32
and is disposed for supplying steam at a reduced rate after the
valve 32 has been closed.
A conduit 38 extends from the wall 22 to the inlet of a positive
rotary blower or pump 40. The outlet of the blower 40 is connected
to one end of a conduit 42 which extends through the bottom wall 20
to a lower portion of the tank 12 and is provided with a check
valve 44 therein. An end of the conduit 42 which is mounted within
the tank 12 is provided with a plurality of apertures 46. Any steam
or moisture laden vapor which accumulates within the chamber 18 is
withdrawn via the conduit 38 and the blower 40 and is advanced into
the lower portion of the tank 12 and released into the slurry 14
through the apertures 46. A release valve 48 is provided in the
upper wall 22 for bleeding any excess of pressure which may result
within the chamber 18.
The conduits 38 and 42 and the blower 40 form a recirculation
system which permits the recovery of heat which is lost in the form
of evaporation and steam or moisture laden vapor escaping from an
upper surface of the slurry 14 to be resupplied to the slurry 14.
It has been the practice in the past to employ a stack or chimney
which extends from the upper wall 22 of the tank 12 to permit the
escape of steam or moisture laden vapor from the cooking slurry. A
heat loss occurs by virtue of the escaping steam or moisture laden
vapor. The present invention, however, accumulates such a steam or
moisture laden vapor within the chamber 18 and recirculates such
steam or moisture laden vapor into the slurry 14 to recover that
heat loss.
In operation, after the slurry 14 has been supplied to the tank 12,
the valve 32 is open to introduce the steam under pressure into the
slurry 14 and the blower 40 is energized to initiate the
recirculation process. When the slurry 14 begins to boil, the valve
32 is closed and the valve 36 is open, such that the rate of steam
supplied via the conduit 30 to the slurry 14 is reduced to an
amount which is sufficient to compensate for any radiant heat loss.
The blower 40 compresses the steam or moisture laden vapor in the
conduit 42, thereby increasing its temperature.
In a constructed embodiment of the present invention, the level 16
of the slurry 14 is at the height of 5 feet above the portion of
the conduit 42 which is within the tank 12. The steam or moisture
laden vapor in the conduit 42 will be presented with a hydraulic
head of approximately 5 feet of liquid. At 0.433 psig per foot, a
compression of 2.17 psig will result. For every one psi
compression, an increase in temperature of approximately 16.degree.
Fahrenheit will result. Accordingly, with 5 feet of liquid as the
hydraulic head, the steam or moisture laden vapor in the conduit 42
will be increased in temperature by approximately 35.degree.
Fahrenheit. Should the blower 40 advance the steam at a rate of 150
cubic feet per minute, it can be readily appreciated that a
substantial amount of heat increase will result. With the above
example, such a heat increase is substantially sufficient to
maintain the slurry 14 at a boiling temperature.
It can be readily appreciated that the steam or moisture laden
vapor escaping from the apertures 46 produce agitation which is
necessary for rupturing the fruit and exposing its pulp to the
boiling or hot water in which it is submerged. It has been found
that less steam is required to produce the same yield by employing
the apparatus and method of the present invention.
* * * * *